In the past decade or so, medical, osteopathic and chiropractic practitioners have recognized the widespread need for insoles that are specially adapted to correct various physical problems, such as foot problems or those back problems that can be produced or aggravated by an inequality in the lengths of a person's legs. Generic orthotics have been available, which a person can utilize on a trial and error basis to seek optimal benefit. Because this approach tends to be fairly unsuccessful, the demand for custom-made orthotics has increased significantly.
In one class of custom-made orthotics, molds are produced of each of a person's feet and each orthotic is molded to fit the bottom contour of the corresponding one of that person's :feet. This bottom contour and average thickness of the orthotic are selected to produce the desired medical, osteopathic and physical benefits to the patient. Such a molding process can take a couple of hours or more and the turn-around time to provide the patient with the custom-made orthotic can be a few weeks.
In order to reduce the time needed to produce custom-made orthotics, AMFIT Inc. developed a foot contour measurement machine, called the Footfax Scanner.TM., that includes an array of parallel pins that can each be displaced longitudinally, such that, when a person's foot is pressed into contact with a top side of this array of pins, the longitudinal displacements measure the contour of that person's foot. AMFIT also developed an associated mill that utilizes this contour data to mill a custom-made orthotic from an orthotic blank. Such an orthotic blank is of a material, such as ethyl vinyl acetate (EVA), that is usually slightly compressible, but rigid enough to provide the desired foot support.
In one embodiment of these two machines, the mill is large and noisy and is therefore located in a manufacturing facility that receives the contour information about a particular patient's foot and fabricates the desired orthotic. Although each of these machines is much more efficient than those in earlier orthotic manufacturing processes, there is still an inherent time lag involved whenever the orthotic is manufactured at a site remote from the medical, osteopathic or chiropractic practitioner. It would therefore be advantageous to have an orthotic manufacturing system that can be located on-site at or near the offices of a group of such practitioners.
The AMFIT model 30XX mill was developed for this use. This machine is about four and a half feet tall and has a base that is approximately three feet by three feet. The orthotic blank is mounted vertically (i.e., with that surface, that is to be milled to fit a patient's foot, having its normal oriented vertically). The orthotic blank is moved in an X-Y plane and the milling head moved in a Z-direction to generate the desired contour in a top surface of the orthotic blank. Unfortunately, the particulates, that are produced in tremendous quantities as a necessary by-product of this process, need to be gathered continuously to facilitate throughput. This has required the inclusion of a vacuum system, similar to the shop vacs that are readily available commercially, to draw these particulates away from the orthotic blank and collect them for disposal. Unfortunately, such systems are much noisier than is desired for the environment of a medical, osteopathic or chiropractic practitioner.
It would therefore be advantageous to have a mill that is suitable for use in any of these environments. Such a machine must be quiet and preferably is small enough that it can be used in a room of the size typical of medical suites without requiring the dedication of that room to this single machine.
These noise and size problems for a mill have not arisen previously, because mills were typically located in an industrial environment in which particulates are not collected, but are instead spewed at will onto the mill and the factory floor adjacent to that machine. When the amount of such particulates becomes sufficient to be bothersome, the machinist typically uses a hand broom or air hose to brush or blow the particulates off of the machine onto the floor and then, when the floor is sufficiently covered to be bothersome, to sweep those particulates up and discard them. In general, there hasn't been a need for a quiet mill suitable for use in the quiet, clean environment characteristic of a doctor's office.